Update some of the OCaml examples so that they run successfully with `make check-ocaml-examples` (important for the CI). Some of the examples were written to depend on passed arguments. Temporarily disable the broken std_string example.
git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@4687 626c5289-ae23-0410-ae9c-e8d60b6d4f22